How Much is Global Warming Slowing Down Runners

Posted on 14 May, 2019 by Vania Nikolova

We’ve analyzed 4,307,567 marathon results from 1,727 marathons. In our previous article, we concluded that American runners have never been slower. In this article, we look at the how much of the slow down is caused by increasing temperatures.


global warming effects on runners


Global temperature increase

We used the data from The National Oceanic and Atmospheric Administration to estimate the rate at which the average annual temperature is changing. We established that the average yearly temperature is changing by 0.07 degrees Fahrenheit. This might seem like a negligible change, but it has its effects.  


temperature trends


What's the optimal temperature for running?

From our marathon results, we estimated the optimal temperature for running a marathon at 42.7 degrees Fahrenheit (5.9 degrees Celcius). 


 optimal temperature for running


10.6% of the slow down of runners is caused by global warming

As we can see the relationship between finish time and the temperature is not linear. For the sake of simplicity, we estimated the average change in speed corresponding to one-degree change in outside temperature. 

Every degree Fahrenheit change in outside temperature results on average in 01:05 minutes change in finish time. Combining both findings we can conclude global warming accounts for 5 seconds slow down every year. The average American adds 43 seconds to his finish time every year. So, in general, Global Warming is responsible for 10.6% of the total slow down. 


About The Researchers

The study is a product of collaboration between Jens Jakob Andersen and Vania Andreeva Nikolova. Andersen is a former competitive runner and statistician from Copenhagen Business School. Nikolova holds a Ph.D. in Mathematical Analysis.



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Vania Nikolova

Vania holds a Ph.D. in Mathematical Analysis and is passionate about data, which allows her to dig deep to and uncover hidden trends. She is deeply passionate about Obstacle Course Racing (OCR), and has earned a Spartan Trifecta medal. With 10 years of experience in weightlifting and martial arts and over 200+ books read on nutrition and dieting, she brings unrivaled expertise and critical perspective on all things exercise and training. Her work has been featured on NPR, Washington Post, Shape, Prevention and many others.